Multiple unit filter



Nov. 5, 1940. J CANTW 2,220,706

MULTIPLE UNIT FILTER Filed Jan. 10, 1959 v INVENTOR EUGENE J CANT/NATTORNEY Patented Nov. 5, 1940 FAT MULTIPLE UNIT FILTER Eugene J,Cantin,

Application January 10, 1939, Serial No. 250,089 11 Claims. (chard-164)This invention relates to the filtering of fluids generally, whetherliquid or gases, but is more specifically designed to operate on'liquidssuch as crank case oil, sugar cane juice, etc.

The main object of the invention is to prolong the efllcient action ofsuch a flltering apparatus by making it in the form of a plurality ofsepa rate units which will be automatically brought intoaction-sequentially as one or another of said units becomes clogged-withaccumulated .solid impurities which it has strained out of the'fluid'that has run through it, and thepreferred method of securing that resultis to make such separate units relatively movable and then utilize themotion of one which is produced bythe increased fluid pressure on it,resulting from increased clogging of its filter membranes, to'o'pen thefeed connection to another, and therefore-less used andlessclogsedlmitpd v 1 The best form of apparatus embodying my inve'ation at presentknown tome is illustrated in the accompanying sheet of drawings in whichFig. 1 is a vertical section of a multi-unit filter shown suspended fromsupply and discharge pipes, the parts being shown in full' lines inposition for operation of the first or lower unit only.

Fig. 2 is a similar view with parts broken away showing certain of thepartsin the positions for a filtering operation through the. second,upper unit,and

Fig. 3 is a cross section on line 3-3 of Fig; 1.

Throughout the drawing like reference characters indicate like parts. VI I I indicates a section of a supply pipe for a filtering system and'ithe pipe for carrying away the filtered fluid discharged therefrom. Theportion of such filtering system here shown comprises a casing indicatedgenerally by 3,-which is suspended from such piping by its inlet andoutlet connections therewith. Such connections, comprise the nipple orshortcoupling 8 having a'thread at one end for screwing into the boss Iton casing cover 4 and another thread at its other end for screwing intothe T-coupling 5 of pipe 2, together with a short pipe section! screwedinto a T-coupling I on pipe I at one end and at the other into boss IIon cover 4. Into the lower part of the opening through this, boss isalso screwed the pipe l2, by which the upper filter' unit indicatedgenerally at if!v is directly supported, while the lower filter unitindicated genorally at I! depends from a second pipe l4 which has a goodworking substantially liquid-tight fit in II. The two filter units areenclosed in a chamber i, by the casing shell-3' volutions extendingparallel to the tie rods.

which screws into the internally threaded flange,

or annular lip, IS, on the under sideof cover 4.

'scopesinto or out of tube l2,'and I5 is biased 4 toward I3- bycompression spring 43 confined between the bottomor closed end of easing3 and the adjacent end plate 30 of said unit [5.

Portsin the wall of tube l2 near its upper end are indicated at'29,29;;and 39, 39, indicate pawls pivoted at 40 near the upper end of tubeH which are biased by spring 44 to'engage the upper edges of twoopposite ports when tube l4 and unit i5 carried thereby are forceddownward far enough against the resistance of spring 43.1 r 1 The twofilter units l3 and I5 are substantial duplicates in details ofconstruction. The upper one l4 comprisesthe strainer cylinder 26 ofperforated metal held between top plate-2ll having downwardly extendingflange or annular lip 2| and bottom plate having a similar upwardlyextendinglipi23, by meansof tie rods 24, 24, fast at one end in thelower-plate and having threaded upper ends projecting through the topplate to carry thumb nuts 25, -25. Within the perforated container soformedis the cylindrically'arranged filtering element 21, formed ofarelatively thin but self-supporting sheet of suitable material (usuallya felt) V bentinto a series of zigzagtcon- Within such cylindricalfilter element is the distributing flange 28- carriedon pipe l2 justbelow ports 29. Centrally perforated plates 20,22, and flange all have atight friction fit on the ex'-' terior of tube or pipe l2. 1 P v i a Thelower unit comprises a similar casing formed by perforated metalcylinder 36, held between bottomiplate 30 having annular lip'3l and topplate 32 having annular lip33, by tie rods 34, 84, fast at one endin'said top plate and projecting through the bottom plate to'en'gagethumb nuts 35,- 35 In this casingfis" confined a filter element 31similar to" 21, and within that is the deflecting plate,- or flange, orspreader 38 carried on and extending across the lower end of'tube i4, Toprevent this lower unit being moved radially of casing 3 so as tojam'tube' 14 in tube I2, I may rivet guide lugs 42, 42, on the exteriorof cylinder" 36 shaped as to slidealong the interior of shelli.

Ports 4|, 4|,in the lower portion'of tube "l4 open into theinterior ofthe lowerunit l5 immediately above deflector plate 38. Top plate 32 isfast on thelower portion or tube l4, Just above 5;

the ports 4|, 4|, so that the whole lower unit is supported from, andmoves with said tube.

In constructing and operating the above described embodiment of myinvention spring 43 is so designed that when installed it will normallyhold unit IS in the raised position indicated in full lines in Fig. 1against any unbalanced pressure of fluid entering said unit from feedpipe I through tubes [2 and [4. In such position the upper end of tubel4 closes ports 29, 29, in tube l2, as shown in Fig. 1, so that anyaccess of the fluid to the interior of the upper unit I3 is then cutoil. Accordingly all the entering fluid passes through the ports 4|formed in the walls of tube l4 out onto the spreader plate or flange 38and thence to the inner surface of the filter element 31, down along thewalls of which it runs until whatever part of it has not been forcedthrough the filter walls reaches the bottom plate 30. The portion whichhas been forced through the filter element and the perforations in themetal cylinder 36 outinto the chamber 5 passes upward through the outletconnection 8 into discharge pipe 2.

When, however, the filter element 3! has become sufiiciently cloggedwith solid material filtered out of the incoming fluid the pressure ofthe latter within this lower unit l5 increases and gradually overcomesthe resistance of spring 43. As a result the lower unit l5 moves slowlydownward (as indicated in dot-and-dash lines in Fig. 1) carrying with itthe single tube l4. when such downward movement of the upper end of saidtube begins to open ports 29 in outer tube l2 a portion of the. incomingfluid is thereby admitted to the interior of the upper filter unit 13and forced by deflecting plate 28 to travel down the inner surfaces ofthe convolutions of filtering element 21, through the Walls thereof andthrough the perforated cylinder 26, into the surrounding portion of theinterior of casing 3. Thence it fiows upward and out. through coupling 8to pipe 2 along with whatever filtrate is still coming up from thepartially clogged lower unit l5. As the clogging of such lower elementincreases the fluid pressure on the bottom plate 30 of said lower unitl5 similarly increases and spring 43 is further compressed, therebypermitting tube 14 to move farther and farther down, until ports 29 arecompletely opened and pawls 39 drop into engagement with the upper edgesof two of them to hold the parts in such finally assumed position. Thisautomatically produced adjustment of the parts gives the fiuid the samefreedom of access tothe upper unit as to the lower one, and theoperation thereafter continues until the former is also clogged sobadlyas to reduce filtering efficiency of the apparatus as a whole to a pointthat renders cleaning and/or replacement of the filter elementsnecessary.

Thereupon the supply can be shut oil, the easing shell 3 unscrewed fromcasing cover 4 and removed, together with filter unit I5, tube I4sliding out of tube l2. Theseparated units can then be taken apart byloosening the thumb nuts 25 and 35, fresh filtering elements 21 and 31substituted for the clogged ones, the other parts cleaned, and all puttogether again and the several units reassembled in the casing, as shownin Fig. 1, for a resumption of filtering operation.

It'over plate 4 can be removed from its supports by using a pipe wrenchto turn both nipples 8 and 9 in such direction as to unscrew them fromthe bosses l0 and II on said plate and so release the entire unit.

Then,

While I have shown only two filter units connected together, theapplication of the principles of my invention is not limited to suchnumber. Also various changes could be made in the details of theconstruction shown and certain features thereof omitted, withoutdeparting from the substance of my invention so long as the same generalprinciples of operation and cooperation are retained to a sufiicientdegree and the modified structures so produced are still within thedefinitions outlined in the appended claims, or in some of them.

Having, therefore, described my invention, I claim:

1. In a filtering apparatus, the combination of a plurality of separatedistinct and severally complete filtering cells each provided with abody of filtering material, a common source of fiuid to be filteredadapted to deliver the same under pressure to the cells, a commondischarge receptacle receiving the filtrate from all of the cells, andmeans for utilizing the pressureof the incoming fiuid to efiect deliverythereof to the filtering cells in succession, the said means includingpressure responsive elements associated with said source of fiuid andactuated by back pressure in a clogged cell to which the fiuidflisfiowingto deliver the fluid to another cell through which the flow iscomparatively free.

' 2. In a fluid filtering apparatus the combination of a plurality ofseparate filtering cells movable relatively one to another, a commonsource of fluid to be filtered and a connecttion from said source toeachcell, a common discharge passage from all the cells, and valve meansactuated by the aforesaid cell movement to sequentially deliver to saidcells the fluid to be filtered.

3. In a fluid filtering apparatus the combination of two distinctfiltering units, one of which is movable relative to the other, a commonsource of fiuid to be filtered adapted to deliver the same underpressure, a normally open connection from said source to one unit and anormally closed connection from the source to the other unit, one of theunits being responsive in movement to the inlet pressure of the fluidand movable by such pressure when clogging of the unit opposes free flowthrough the same, and mechanism associated with said movable unit andsaid normally closed connection to open the connection when said unithas moved to a predetermined extent.

4. A combination such as defined in claim 3 in which each of said unitscomprises a cell having walls of filtering capacity, and with theinterior of which said supply connections communicate, and in which saidmechanism comprises telescoping conduit sections in the connection tothe movable unit openings in one of said conduit sections communicatingwith the second mentioned unit and adapted to be uncovered by movementof the other section for the flow of fluid to the last mentioned unit;and a'spring tending to shorten said connection but yieldable to permitit to be lengthened when the mechanism is actuated as hereinbeforedescribed.

5. A construction such as defined in claim 3 combined with means adaptedto automatically lock the parts in the relative positions assumed whensaid normally closed connection has been opened.

6. In a filtering apparatus the combination of a filtering unitcomprising a cell having filtering walls, a'supply pipe extendingthrough said cell and having a port opening into the cell interior, asecond unit comprising a separate cell having filtering wallsand a tubetelescoping at one end into said supply pipe and at the other endopening into said cell interior, together with a spring normally tendingto move said second unit in a direction such as to force its said tubeinto said supply pipe far enough to close the said port in the latterbut capable offlexure in the opposite direction far enough to open saidport, said spring being constructed so as to be flexed in such mannerwhenever the pressure of fluid in said tube reaches a predeterminedamount.

7. A structure such as defined. in claim 6 in which said port is locatednear that portion of the cell wall through which said pipe enters saidcell interior, combined with a deflecting flange on said pipes exteriorlocated adjacent the side of said port most remote from-said wall por-,

tion and extending radially from said pipe nearly to the interiorsurfaces of the adjacent filtering walls of said cell so as todistribute the inflowing fluid directly and evenly to said filtersurfaces.

' 8. A structure such as defined in claim 6 in which the opening fromsaid telescoping tube to the interior of said second cell, is located'inthe tube periphery and near that portion of said cell walls throughwhich said tube extends, combined with a deflecting plate closingtheextreme end of said tube and extending radially therefrom nearly tothe surrounding filtering walls of said cell.

9. A structure such as'defined in claim 6 combined with locking meanspivoted on the end of said telescoping tube adjacent said port which areadapted to engage one edge thereof so as to hold said tube in positionassumed alter a sub-' mechanism for normally biasing said locking meanstoward locking position;

-10. In a filtering apparatus the combination of an elongated tubularcasing and two filtering units contained therein, one of said unitsbeing fixed in one end portion of said casing-and the other being ofless transverse dimensions than,

and movable in, the other end portion thereof,

said movable unit having a valvedconnection to said fixed one whichconnection consists of telescoping sections one connected to the fixedunit and the other to the movable unit for operation ofvthe valve by.the movable unit, and a plurality of transversely extending Vspaced-apart projections on the movable unit-for guiding its movementsin said casing but allowing, fluid to flow freely around them. I H

11. Ina fluid filtering apparatus the combination 01' a tubularstructure having peripheral walls provided with a lining of filteringmaterial, an axially disposed tube of much less diam- 3 stantial openingof said port has occurred, and

star. fixed thereimadapted to be connected'to a source of fluid supply,and having a port in its walls opening into the interior of saidstructure near one end thereoifiand a single fiangefixed on said lastmentioned tube exterior at a' point immediately adjacent the inner edgeof said port and extending nearly to said lining at all points a of itsperiphery; whereby a thin annular sheet of any fluid discharged fromsaid inner tube through its said port is uniformly distributed along andover the entire interior of said filtering lining. a

EUGENE J. CANTIN.

